Is it possible to know if I have to use the method for samples containing > 10 % RS content or the method for samples containing < 10 % RS content when analysing RS content using the Resistant Starch Assay Kit (K-RSTAR)?

This will depend on the type of sample being analysed. Some information about RS content can be found in the scientific literature. If in doubt, you could run on the assumption that the value is 0-10%, then if the value is very high (absorbance values for the sample are higher than the absorbance values obtained for the glucose standard), dilute an aliquot of the solution 10-fold and repeat the GOPOD reaction.

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